Hyalorhinocladiella and Sporothrix are
two common mycelial anamorphs of Ophiostoma that are difficult
to distinguish from each other.
Sporothrix spp. differ visibly from Hyalorhinocladiella
by the presence of denticles on the conidiogenous cells.
Graphium and Sporothrix
are often synanamorphs of the same Ophiostoma species and the
aim of this study was to determine whether a relationship exists
between sympodial conidium development in Sporothrix and
annellidic development in Graphium. Conidium development was
examined in Sporothrix schenckii, Ophiostoma nigrocarpum
and Ophiostoma piceae. Using fluorescence microscopy, as well
as scanning
and transmission electron microscopy, distinct denticles were
observed on the conidiogenous cells in Sporothrix spp. In some
cases,
these conidiogenous cells were reduced, giving them a
Hyalorhinocladiella-like appearance. Results of this study suggest
that a
continuum in patterns of conidium development exists between
Sporothrix, Hyalorhinocladiella and Graphium.
The linear extent, and
the angle of the proliferation stage with reference to the long axis
of the conidiogenous cell, appear to determine the form of
conidium development.